XML 93 R77.htm IDEA: XBRL DOCUMENT
v3.23.1

Ordinary shares (Details) |  |  |  |  |  | 1 Months Ended | 7 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 10, 2020 USD ($) $ / shares shares | Aug. 28, 2018 shares | Dec. 31, 2017 | Dec. 31, 2016 | Jan. 01, 2016 $ / shares shares | May 19, 2019 USD ($) $ / shares shares | Mar. 22, 2018 shares | Jun. 19, 2017 USD ($) $ / shares shares | Sep. 22, 2016 USD ($) shares | Nov. 25, 2015 USD ($) shares | Jan. 31, 2015 | Jan. 28, 2015 USD ($) $ / shares shares | Dec. 31, 2020 shares | Dec. 31, 2022 $ / shares shares | Dec. 31, 2021 $ / shares shares | Dec. 31, 2018 shares | Dec. 31, 2017 CNY (¥) shares | Dec. 31, 2019 shares
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Prior to the completion of the IPO (in Dollars) | $ |  |  |  |  |  | $ 50,000 |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized |  |  |  |  |  | 50,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, par or stated value per Share (in Dollars per share) | $ / shares |  |  |  |  |  | $ 0.001 |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares, outstanding |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 232,451,900
Vesting period |  |  |  |  |  |  |  |  | 4 years |  | 5 years |  |  |  |  |  |  |
Ordinary shares repurchased |  |  |  |  |  |  |  | 8,630,140 |  |  |  |  |  |  |  |  |  |
Ordinary shares repurchased price per share (in Dollars per share) | $ / shares |  |  |  |  |  |  |  | $ 0.96 |  |  |  |  |  |  |  |  |  |
Ordinary shares repurchased, amount (in Dollars) | $ |  |  |  |  |  |  |  | $ 8,297,880 |  |  |  |  |  |  |  |  |  |
Reduction of additional paid in capital for cancellation of repurchased ordinary shares (in Dollars) | $ |  |  |  |  |  |  |  | $ 8,298,236 |  |  |  |  |  |  |  |  |  |
Cumulative revenue (in Yuan Renminbi) | ¥ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | ¥ 500 |
Number of shares issued upon conversion |  | 35,004,220 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares were issued upon vesting of restricted share |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,767,180 |  |  |  |
Prior to the Completion of the IPO [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued upon conversion | 122,072,980 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Authorized share capital increased (in Dollars) | $ | $ 50,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized | 1,000,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividend price per share (in Dollars per share) | $ / shares | $ 0.00005 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividend (in Dollars) | $ | $ 100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock dividend shares | 2,000,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Price per share (in Dollars per share) | $ / shares | $ 0.00005 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2018 Stock Option Scheme [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Conversion of shares, basis |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 55,980,360 |  |
Ordinary Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred shares, per value (in Dollars per share) | $ / shares |  |  |  |  |  | 0.00005 |  |  |  |  |  |  |  |  |  |  |  |
Treasury Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares issued |  |  |  |  |  |  | 31,665,280 | 4,315,080 |  | 20,000,000 |  |  |  |  |  |  |  |
Series A Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares transferred |  |  |  |  | 4,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares transferred fair value per share (in Dollars per share) | $ / shares |  |  |  |  | $ 0.88 |  |  |  |  |  |  |  |  |  |  |  |  |
Class A Ordinary Shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,700,000,000 | 1,700,000,000 |  |  |
Common Stock, par or stated value per Share (in Dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.00005 | $ 0.00005 |  |  |
Common stock, shares, outstanding |  |  |  |  |  |  |  |  |  |  |  |  |  | 246,686,120 | 164,975,400 |  |  |
Shares were issued upon exercise of outstanding stock options |  |  |  |  |  |  |  |  |  |  |  |  | 576,720 |  | 1,919,760 |  |  |
Shares were issued upon vesting of restricted share |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,000,000 |  |  |
Ordinary Shares were issued for convertible debenture |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 |  |  |  |
Aggregate shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 76,943,540 |  |  |  |
Class A Ordinary Shares | Prior to the Completion of the IPO [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of votes per ordinary share | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class A Ordinary Shares | IPO [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares, outstanding | 159,478,920 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares issued | 20,100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares converted into Class A ordinary share | 110,378,920 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares issued and sold price per ADS (in Dollars per share) | $ / shares | $ 18 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred shares converted into ordinary shares | 29,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class B Ordinary Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized |  |  |  |  |  |  |  |  |  |  |  |  |  | 200,000,000 | 200,000,000 |  |  |
Common Stock, par or stated value per Share (in Dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.00005 | $ 0.00005 |  |  |
Common stock, shares, outstanding |  |  |  |  |  |  |  |  |  |  |  |  |  | 122,072,980 | 122,072,980 |  |  |
Class B Ordinary Shares [Member] | Prior to the Completion of the IPO [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of votes per ordinary share | 15 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class B Ordinary Shares [Member] | IPO [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares, outstanding | 122,072,980 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
ADS [Member] | IPO [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares issued | 2,010,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Chaohui Chen [Member] | Class B Ordinary Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares, outstanding | 61,346,560 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Zhiping Peng [Member] | Class B Ordinary Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares, outstanding | 60,726,420 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, par or stated value per Share (in Dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  | $ 0.00005 |  |  |  |  |  |
Common stock, shares, outstanding |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 162,897,778 |  |
Vesting period |  |  |  |  |  |  |  |  | 4 years |  |  | 5 years |  |  |  |  |  |
Ordinary shares, vested |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 44,426,667 | 44,426,667 |
Board of Directors Chairman [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, par or stated value per Share (in Dollars per share) | $ / shares |  |  |  |  |  | $ 0.00005 |  |  |  |  |  |  |  |  |  |  |  |
Shares subdivided, number of shares |  |  |  |  |  | 20 |  |  |  |  |  |  |  |  |  |  |  |
Series A Share Purchase Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares issued |  |  |  |  |  |  |  |  |  |  |  | 8,400,000 |  |  |  |  |  |
Ordinary shares issued, total consideration (in Dollars) | $ |  |  |  |  |  |  |  |  |  |  |  | $ 4,056,206 |  |  |  |  |  |
Series A Share Purchase Agreement [Member] | Series A Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares issued |  |  |  |  |  |  |  |  |  |  |  | 25,000,000 |  |  |  |  |  |
Ordinary shares issued, total consideration (in Dollars) | $ |  |  |  |  |  |  |  |  |  |  |  | $ 9,788,652 |  |  |  |  |  |
A-1 SPA [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares issued |  |  |  |  |  |  |  |  |  | 26,575,220 |  |  |  |  |  |  |  |
Ordinary shares issued, total consideration (in Dollars) | $ |  |  |  |  |  |  |  |  |  | $ 21,555,470 |  |  |  |  |  |  |  |
Ordinary shares redemption price compounded annual interest rate |  |  |  | 10.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
A-2 SPA [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares issued |  |  |  |  |  |  |  |  | 8,502,600 |  |  |  |  |  |  |  |  |
Ordinary shares issued, total consideration (in Dollars) | $ |  |  |  |  |  |  |  |  | $ 10,000,000 |  |  |  |  |  |  |  |  |
Ordinary shares redemption price compounded annual interest rate |  |  | 12.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

X
- Definition Adjustments to additional paid in capital cancellation of repurchased ordinary shares. + References No definition available. + Details
Name: | ucl_AdjustmentsToAdditionalPaidInCapitalCancellationOfRepurchasedOrdinaryShares
Namespace Prefix: | ucl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Number of share aggregate. + References No definition available. + Details
Name: | ucl_AggregateShares
Namespace Prefix: | ucl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of authorized share capital increased. + References No definition available. + Details
Name: | ucl_AuthorizedShareCapitalIncreased
Namespace Prefix: | ucl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Common stock authorized amount. + References No definition available. + Details
Name: | ucl_CommonStockAuthorizedAmount
Namespace Prefix: | ucl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Cumulative revenue. + References No definition available. + Details
Name: | ucl_CumulativeRevenue
Namespace Prefix: | ucl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | ucl_NumberOfVotesPerOrdinaryShare
Namespace Prefix: | ucl_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Ordinary shares redemption price compounded annual interest rate. + References No definition available. + Details
Name: | ucl_OrdinarySharesRedemptionPriceCompoundedAnnualInterestRate
Namespace Prefix: | ucl_
Data Type: | dtr:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Ordinary Shares were issued for convertible debenture. + References No definition available. + Details
Name: | ucl_OrdinarySharesWereIssuedForConvertibleDebenture
Namespace Prefix: | ucl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | ucl_OrdinarysharesDetailsLineItems
Namespace Prefix: | ucl_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Shares transferred. + References No definition available. + Details
Name: | ucl_SharesTransferred
Namespace Prefix: | ucl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Shares were issued upon exercise of outstanding stock options. + References No definition available. + Details
Name: | ucl_SharesWereIssuedUponExerciseOfOutstandingStockOptions
Namespace Prefix: | ucl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | ucl_SharesWereIssuedUponVestingOfRestrictedShare
Namespace Prefix: | ucl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Stock issued during period, shares, conversion of preferred stock. + References No definition available. + Details
Name: | ucl_StockIssuedDuringPeriodSharesConversionOfPreferredStock
Namespace Prefix: | ucl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Stock issued during period, shares, redesignation of ordinary shares. + References No definition available. + Details
Name: | ucl_StockIssuedDuringPeriodSharesRedesignationOfOrdinaryShares
Namespace Prefix: | ucl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Stock issued during period shares subdivided. + References No definition available. + Details
Name: | ucl_StockIssuedDuringPeriodSharesSubdivided
Namespace Prefix: | ucl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Stock repurchased price per share. + References No definition available. + Details
Name: | ucl_StockRepurchasedPricePerShare
Namespace Prefix: | ucl_
Data Type: | dtr:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Aggregate number of common shares reserved for future issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_CommonStockCapitalSharesReservedForFutureIssuance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Face amount or stated value per share of common stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_CommonStockParOrStatedValuePerShare
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_CommonStockSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_CommonStockSharesOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4332-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4304-108586 + Details
Name: | us-gaap_DebtConversionConvertedInstrumentSharesIssued1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 405 -Section 45 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 + Details
Name: | us-gaap_DividendsCash
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The per share amount of a dividend declared, but not paid, as of the financial reporting date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4304-108586 + Details
Name: | us-gaap_DividendsPayableAmountPerShare
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Maximum number of excess stock shares permitted to be issued. + References No definition available. + Details
Name: | us-gaap_ExcessStockSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644 + Details
Name: | us-gaap_PreferredStockParOrStatedValuePerShare
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction. + References No definition available. + Details
Name: | us-gaap_SaleOfStockPricePerShare
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(02) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Price of a single share of a number of saleable stocks of a company. + References No definition available. + Details
Name: | us-gaap_SharePrice
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Per share or per unit amount of equity securities issued. + References No definition available. + Details
Name: | us-gaap_SharesIssuedPricePerShare
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of shares of common and preferred stock issued as dividends during the period. Excludes stock splits. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644 + Details
Name: | us-gaap_StockDividendsShares
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of shares issued during the period as a result of the conversion of convertible securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29-30) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1E -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21475-112644 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644 + Details
Name: | us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of new stock issued during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Value of stock issued in lieu of cash for services contributed to the entity. Value of the stock issued includes, but is not limited to, services contributed by vendors and founders. + References No definition available. + Details
Name: | us-gaap_StockIssuedDuringPeriodValueIssuedForServices
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_StockRepurchasedDuringPeriodShares
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_StockRepurchasedDuringPeriodValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | srt_RestatementAxis=ucl_PriorToTheCompletionOfTheIPOMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PlanNameAxis=ucl_TwoThousandEighteenStockOptionSchemeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_CommonStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_TreasuryStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_SeriesAPreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=us-gaap_IPOMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassBMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=ucl_AmericanDepositorySharesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=ucl_ChaohuiChenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=ucl_ZhipingPengMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_TitleOfIndividualAxis=srt_BoardOfDirectorsChairmanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=ucl_SeriesASharePurchaseAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=ucl_SeriesA1SharePurchaseAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=ucl_SeriesA2SharePurchaseAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |